Shuttle propelling mechanism for looms



March 27, 1962 w. WADE 3,026,912

SHUTTLE PROPELLING MECHANISM FOR LOOMS Filed Maroh 12, 1958 United States Patent ()fifice 3,Zh,9l2 Patented Mar. 2?, 1962,

3,026,912 SHUTTLE PRUWELLING MECHANISM FOR LOOMS Worth Wade, Rosenront, Pa, assignor to American Viscose Corporation, Philadelphia, Pa, a corporation of Delaware Filed Mar. 12, 1958, Ser. No. 720,910 13 Claims. ((11. 139-142) The invention relates to explosive powered shuttle mechanisms, and particularly to an apparatus for regulating the movement of a reciprocating shuttle propelled by arrangements as described in my United States Patents 2,682,895 and 2,784,743.

In my prior patents noted, there is described for the first time mechanisms for looms whereby a shuttle may be propelled along its reciprocating path by the impact of an explosive material, which may be either in a solid, liquid, or gaseous form. As a result of these inventive teachings, the long sought aims of the textile industry of increased production speeds and woven fabrics of greater width may now be realized.

Weaving with conventional looms is somewhat restricted 'by the speed of the loom shedding mechanism which, as understood by those skilled in the art, operates a harness to separate the warp threads and form a shed for the passage of a shuttle. The shedding mechanisms of existing looms thus require a definite and unvarying time period to effect harness reciprocation before the shuttle is again passed through the weaving shed. However, it is highly desirable to incorporate into conventional loom constructions, the advantageous and novel shuttle propelling systems disclosed in my United States patents, and therefore it is a primary object of the present invention to provide arrangements for regulating the reciprocating travel of an explosively propelled shuttle.

Another object of the invention is to provide an apparatus for propelling a shuttle through a loom at pre-- determined time intervals.

Still another object is to provide means for effecting a time delay between successive reciprocating passes of an explosively propelled shuttle to enable the loom shedding agency to perform its intended function.

Still another object is the provision of means for partially absorbing the initial impact of an exploding shuttle propelling medium.

A further and more specific object of the invention is to provide means for adapting an explosively powered shuttle to existing loom constructions.

These and other objects and advantages of the invention will be apparent from the following description and accompanying drawing in which:

FIGURE -1 is a diagrammatic illustration of a shuttle driving mechanism incorporating a mechanical arrangement for delaying shuttle propulsion after each of its successive reciprocating passes across a loom;

FIGURE 2 is a diagram of an electronic circuit for regulating explosive detonation of the shuttle driving mechanism shown in FIGURE 1 to predetermined time intervals;

FIGURE 3 is a diagram of an alternative electrical circuit employing a thermistor element;

FIGURE 4 is a diagrammatic representation of one end of a shuttle propelling mechanism employing an impact absorbing arrangement for controlling the shuttle acceleration; and

FIGURE 5. is a fragmentary view, partly in section, of a modified impact absorbing means.

The shuttle propelling mechanisms, with or without the time delay and impact absorbing arrangements of the present invention, may be used with any type of weaving machine, or loom, regardless of whether or not they are convertible looms or non-convertible looms having shuttle magazines. Likewise, it may be used with shuttles which do not carry a bobbin but which are provided with means for gripping the end of the filling yarn and carry it across the weaving machine by drawing the yarn directly from a large package. It will be further understood that the teachings of the invention disclosed herein are equally adapted for use with any of the various modifications. of shuttle propelling means disclosed in my above noted patents.

According to the present invention, there is provided a shuttle driving mechanism for looms comprising means for reciprocating the shuttle through the weaving shed between first and second positions by means of an'ex plosive force, time delay means actuated by the movement of the shuttle itself for controlling explosive detonations to a predetermined sequence, and means for partially absorbing the explosive impact so as to regulate the initial speed of the shuttle as it is propelled from one of the first or second positions.

In one embodiment of the invention, the time delay mechanism comprises a mechanical arrangement which includes a pair of articulated arms set in motion by the movement of the the shuttle itself and serving to oscillate a rotatable disk. A contact is carried on the periphery of the disk and engages with a detonating mechanism after the disk has oscillated through a predetermined arc. In the second embodiment of the invention, a thyratron, cooperating with a pulse forming network, serves to energize a spark plug through a conventional ignition coil, while in the third embodiment, detonation control is obtained through an electrical circuit containing a bead thermistor. Since the yarn carried or gripped by the shuttle has a tendency to break or at least become weakened if the shuttle is initially propelled at too rapid a speed, the invention also relates to means for partially absorbing the explosion impact, which in one embodiment consists of an energy dissipating spring, and in a second embodiment as a double acting dashpot.

Referring to FIGUE 1, there is shown one example of a shuttle driving mechanism wherein a liquid propellant is utilized for driving a shuttle 14 through its reciprocating path. As heretofore mentioned, the shedding mechanism operates to form a weaving shed which extends across the loom and through which the shuttle is propelled. At each end of the weaving shed there is a duplicate structure comprising a shuttle receiving box normally having spring loaded walls which snugly engage with the shuttle and retard its forward movement. The shuttle driving device per se comprises a cylinder or combustion chamber 15 within which a piston 17 is reciprocated by a rod 19. The piston rod 1% extends through the end wall of the combustion chamber 15 and terminates with a shuttle receiving cup 21, shaped to conform to the tapered end of the shuttle 14. As with the usual internal combustion engines, the cylinder 15 is provided with exhaust ports, not shown, which remain closed during the explosion but open as the piston rod 19 is urged into its outermost position as shown at the right side of FIGURE 1.

With the embodiment illustrated in FIGURE 1, a fiuid propellant is introduced into the chamber 15 through a delivery line 23 and a metering valve 25, the latter of which is actuated by articulated arms 27 and 259. The arm 29 and piston rod 19 are connected at so to coordinate the fluid propellant delivery with the movement of the piston rod 19. Detonation of the fiuidpropellant introduced into the cylinder 15 may be accomplished by any suitable menas, such as an electric spark, an instan However, for the sake of illustration and ease of description, the detonating means is shown as a conventional spark plug 31, electrically connected to a suitable source by wires 33 and having an energization switch 35.

Energization or triggering of the spark plug 31 at the exact desired instant is effected through articulated arms 37 and 39, which are pivotally secured to each other at 41 and slidably connected to a rotatable disk 43. The arm 37 is attached to the piston rod 19 at 45, while the slidable connection between the arm 39 and the disk 43 includes a pin or shoe 47 fixed to the end of the arm 39 and adapted to ride within an arcuate slot 48 formed in the disk 43. A pin or contact 49 projects outwardly from the periphery of the disk 43 and serves to complete the electrical circuit to the spark plug 31 through the switch 35 when it engages therewith.

With reference to the left hand side of FIGURE 4, it will be apparent that as the shuttle 14 first enters the cup 21, the piston rod 19 will be in its outer-most position with respect to the cylinder 15 and the pin 47 will be engaged with the left end of the slot 48. As the piston rod moves through its compression stroke, the pin 47 will urge the disk 43 in a counterclockwise direction. Concomitantly with the compressive movement of the piston rod 19, the exhaust ports are closed and the arms 27 and 29 operate the metering valve 25 to introduce a unit quantity of propellant into the chamber 15. Once the compression stroke is completed, the pin 47 will of course stop. The disk 43, however, will continue its counterclockwise movement under its own momentum until the right end of the slot 48 engages with the pin 47. This continued movement of the disk 43, after the pin 47 has stopped, serves to move the contact 49 into engagement with the switch 35 and thus provides a desired time delay between the end of the compression stroke and the actual detonation of the propellant delivered by the line 23. At the instant of explosion, the shuttle 14 is driven across the lay board and through the weaving shed to the opposite side of the loom, Where it automatically actuates a propelling mechanism and detonation time delay device in the same manner as just described.

As the piston rod 19 at the left side of FIGURE 1 moves toward its outermost position during the propellant explosion, the pin 47 will time the disk 43 in a clockwise direction. Once this expansion stroke is completed, the piston rod 19 and the pin 47 will of course stop. The momentum of the disk 43, however, will again cause the disk 43 to continue its movement until the left end of the slot 48 is engaged with the pin 47. It will be thus noted that the momentum of the disk 43, during its clockwise movement, moves the same in a desired position for actuation during the compression stroke.

One important aspect of the present invention is the control maintained over the propellant detonating means. This insures that the explosion occurs at the desired instant, and only after a predetermined period of time has elapsed after the piston .rod 19 is initially started along its compressive stroke. .It will be observed that while the piston rod 19 is moved fairly rapidly through its compressive stroke, the actual detonation of the fluid propellant is delayed until the contact or pin 49 engages with the switch 35. With this arrangement, the shuttle 14 remains at one end of the lay board for a time period suflicient to allow the loom shedding mechanism to perform its necessary function. The required momentary pause of the shuttle will depend, for example, upon the particular loom employed and therefore it may be desirable to alter the detonation delay time, for instance, by relocating the contact 49 relative to the disk periphery and/ or by providing the disk 43 with a desired weight so as to regulate its momentum, and/or by altering the length of the slot 48.

In lieu of the mechanical arrangement illustrated in FIGURE 1, control of the fluid propellant detonation may be also obtained by an electronic time delay network as illustrated in FIGURE 2. The diagrammatic representation of FIGURE 2 actually consists of a number of individual circuits or networks which, when combined, provide the desired time delay system. Therefore, for ease of description, the circuit of FIGURE 2 has been broken down into a series of networks denoted as A, B, C and D. The network A includes an electric source 49 and a switch 51, the latter of which is disposed along the shuttle path and is actuated by the shuttle as it reciprocates to and from its terminal positions. A resistor 53 and a capacitor 55 form the circuit shown at B, while the amplitude comparator and trigger, network C, includes a thyratron 57 having its grid 59 biased by a resistor 61 and battery 63 and electrically connected with the resistor capacitance circuit B. The thyratron plate 65 controls the ignition circuit D comprising a pulse-forming network 67, consisting of a coil 69 and a capacitor 71, a conventional ignition coil 73, and the spark plug 31. The thyratron cathode 75 is heated in a conventional manner while the plate 65 is connected to a suitable voltage source through a resistor 76.

In the operation, the movement of the shuttle 14 toward and into one of its terminal positions actuates the switch 51 and completes the electrical circuit to the thyratron 57. After a desired and preselected time interval, the thyratron 57 is triggered to energize the spark plug 31 through the pulse-forming network 67 and the ignition coil 73.

For proper timing of the triggering of the thyratron, the components of the pulse-forming network (coil 69 and capacitor 71) are so selected that the characteristic impedance (LC) of the network is relatively small with respect to the resistance of plate resistor 76, of the order of about one-tenth of the resistance of the plate resistor 76, and the resistor 76 and capacitor 71 are so selected that the time constant (RC) is relatively small with respect to the time interval between closings of the switch 51, of the order of about one-fifth of such time. With both of these factors being satisfied, the trailing edge of the pulse, defined by the inductor 69 and 71, working into the coil or load 73 effects a quenching of the thyratron 57 at the desired time after the propellant explosion has taken place.

Variation in the detonation time delay may be obtained by changing the electrical components, such as the thyratron tube 57, or by altering the position of the switch 51 along the loom lay board. As the shuttle is explosive- 1y propelled out from one of its terminal positions, its movement against theadjacent switch 51 opens the electrical circuit, and it is therefore apparent that this second modification of the invention facilitates the desired shuttle pause at the end of each of its reciprocating passes, and frrther maintains the synchronous passage of the shuttle by relying upon the shuttle itself for opening and closing the time delay electric circuit.

A third embodiment of the present invention is illustrated by the circuit of FIGURE 3, wherein an electric source 77 serves to operate a relay 79 through a bead thermistor 81 when a switch 83 is closed by the shuttle 14. The relay 79 actuates the ignition circuit, such as shown at D in FIGURE 2, to energize a spark plug and set off the explosion of the fluid propellant. As generally understood, a thermistor has a very high negative temperature coefficient of resistance, and thus its current conducting capacity increases with its temperature. Therefore, while the movement of the shuttle closes the switch 83 to complete the electrical path, spark plug energization is delayed until the thermistor is heated to such a degree as to conduct suflicient current to actuate the relay 79. To eliminate any tendency for the thermistor to destroy itself, a tungsten lamp 85 is interposed in series with the thermistor and the relay for consuming any excess electrical energy. As with the last described embodiment of the invention, the electrical circuit components of FIGURE 3 may be changed to vary the period of detonation delay, or alternatively the switch- 83 may be relocated relative to the loom lay board.

As heretofore mentioned, initial propulsion of the. shuttle from its terminal positions at too rapid, a speed has a tendency to snap the yarn filling carried by the shuttle, thereby breaking or undesirably weakening the same. To eliminate this objection, I have provided means for absorbing a portion of the explosion impact so as to control the initial speed of the shuttle as it leaves its terminal positions. These means are illustrated in FIGURES 4 and 5 and may be used with explosive propelling mechanisms as described in my recently issued patents or as disclosed in the present application, regardless of whether or not such mechanisms are provided with a time delay system as shown in any of the FIGURES l3. For the sake of consistency, however, these impact absorbing devices are hereafter described as being applied to the propelling mechanism shown in FIGURE 1. With reference to FIGURE 4, the arrangement there shown includes a coiled compression spring 87 encircling the piston rod 19 and secured at its ends to stop plates 89 and 91. The plate 8h is fixed at 93 to the piston rod 19, while the plate 91 is carried by but slidable relative to the piston rod for purposes as hereafter described. As the shuttle 14 enters its terminal position shownin FIGURE 4, the piston rod 19 moves through its compressive stroke, carrying with it the stop plates 89 and, 91 and the coil spring 87. During this movement, the stop plate 85 rides along a bearing surface 95 of a lever 97 pivoted to a fixed support 99, thereby tilting the lever 97 in a counterclockwise direction against the action of a tension spring 101 and elevating a pawl 163 into position as shown in FIGURE 4. Preferably, a spring, not shown, maintains the pawl 103 in its upright position as shown and allows the same to be depressed only as the plate 91 moves to the left.

As the fluid propellant is exploded within the cylinder 15, the piston 17 and rod 1)- are urged through their explosive stroke to propel the shuttle 14 to the other of its extreme positions. With this outward travel of the piston rod 19, the movement of the stop plate 91 is obstructed by the pawl 103, while the stop plate 89 continues to move with the rod 19, thereby compressing the spring 87 between the plates 89- and 91. The explosive impact is thus utilized to both compress the spring 87 and propel the shuttle 14, thereby insuring that the shuttle will be started on its flight at a lower speed than heretofore possible with an explosive driving means. As the stop plate 89 moves slightly to the right of its dotted line position shown in FIGURE 4, it leaves the surface 95, allowing the spring 101 to pivot the lever 97 clockwise and disengage the pawl 103 from the stop plate 91. The spring 37 then expands into its equilibrium condition, dissipating its stored energy. While the impact absorbing arrangement disclosed in FIGURE 4 serves well to cushion a portion of the thrust of the exploding fluid, it will be observed that this arrangement does not retard the movement of the piston rod 19 through its compressive stroke, and therefore does not impair or in any way modify the normal function of the explosive propelling mechanism or its detonation time delay system.

The alternative impact absorbing means disclosed in FIGURE 5 includes a piston 167 fixed to the piston rod 19 which passes through the end walls of a cylinder 109. The cylinder 16? is filled with a hydraulic fluid 111 while the piston 167 is provided with a series of apertures 113. The structure of FIGURE 5 is, in effect, a double acting dashpot, and during use the explosive impact is used to both drive the piston 107 and rod 19 to the right and force the hydraulic fluid through the piston apertures 113 from one side of the cylinder to the other. The excess force is thus dissipated by the fluid and the shuttle is propelled at a desirable starting speed without danger of snapping the filling yarn. An added advantage of this last described structure is that the thrust of the shuttle 14,

as it enters a shuttle receiving cut, is partially absorbed inagain forcing the hydraulic fluid 111 through the piston apertures 113. Therefore, this embodiment has particular utility when a relatively large explosive impact is necessary to propel the shuttle across a wide loom and Where it is necessary to retard the shuttle movement as it enters its terminal position to prevent damage to the explosive propelling mechanism itself.

To reduce noise, the explosive chamber may be provided with a silencer of conventional type as used on ordnance, and to reduce fumes resulting from the explosions, the loom may be provided'with an air exhaust duct which is customary in modern weaving mills.

From the above description, it will be apparent that the detonation time delay devices adapt my explosive shuttle propelling mechanisms for use with conventional loom constructions, and that the impact absorbing means insure satisfactory operation without risk of damage to the filling yarn, the shuttle, or the loom itself.

It is to be understood that changes and variations may be made without departing from the spirit or scope of the invention as defined in the appended claims. While the time-delay mechanism of this invention has been illuctrated in combination with shuttles powered by fluid propellants it isto be understood that the same time-delay means may be used with shuttles powdered by use of solid explosives as described in my prior Patent No. 2,682,895.

This application is a continuation-in-part of my application Serial No. 646,094, filed March 14, 1957, now abandoned.

I claim:

1. A mechanism for propelling a shuttle in a loom be tween first and second terminal positions including a shuttle, means at the first and second terminal positions op-. erative in alternate relationship for exploding a propellant, means at the first and second terminal positions actu ated by such explosion for propelling said shuttle, means actuated by said shuttle as it moves into the first and secend terminal positions for operating said propellant exploding means, and means interposed between said shuttle actuated means and said propellant exploding means for delaying explosion of the propellant for a predetermined time period after said shuttle is received within said first and second terminal positions.

2. A mechanism as defined in claim 1 further including a dashpot for partially absorbing the explosion impact as it is applied to the shuttle.

3. A mechanism for propelling a shuttle in a loom comprising a shuttle, means for exploding a propellant, means actuated by said explosion for propelling said shuttle, a rotatable disk, means carried by said last-mentioned means for oscillating said disk, and means carried by said disk for actuating said first-mentioned means after said disk has been oscillated through a predetermined arc.

4. A mechanism as defined in claim 3 further including a shock absorbing agency positioned adjacent to said shuttle propelling means, and means carried by said shuttle propelling means for transmitting a portion of the explosion impact to said shock absorbing agency.

5. A mechanism as defined in claim 1 further including a shock absorbing agency positioned adjacent to said shuttle propelling means, and means carried by said shuttle propelling means for transmitting a portion of the explosion impact to said shock absorbing agency.

6. A mechanism as defined in claim 1 further including a resilient member disposed adjacent to each of said first and second positions, and means operative by said second mentioned means for transmitting a portion of the explosive impact to the respective resilient members during the initial movement of said second mentioned means to thereby control the initial propulsion of said shuttle.

7. A mechanism for propelling a shuttle in a loom between first and second terminal positions including a shuttle, a detonator at each of the first and second terminal positions operative in alternate relationship for exploding a propellant, means at the first and second terminal positions actuated by such explosion for propelling said shuttle, an ignition coil for energizing each of said detonators, means adapted to be actuated by said shuttle as it moves into the first and second terminal positions for operating said detonators through said ignition coil, and electrical means operatively connected between said shuttle actuated means and said ignition coil for delaying explosion of the propellant for a predetermined time period after said shuttle is received within said first and second terminal positions.

8. A mechanism as defined in claim 7 wherein said electrical means includes a thyratron and a pulse forming network, said thyratron being electrically connected with said shuttle actuated means for operating said ignition coil through said pulse forming network, said pulse forming network serving to quench the thyratron after the explosion of the propellant by said detonator.

9. A mechanism as defined in claim 7 wherein said electrical means includes a thermistor and a relay, said thermistor being electrically connected with said shuttle actuated means for operating said ignition coil through said relay.

10. A mechanism as defined in claim 7 wherein said electrical means includes a thyratron, a resistor-capacitance network electrically connected with the grid of the thyratron and said shuttle actuated means, and a pulse forming network electrically connected to the plate of said thyratron and said ignition coil for quenching the thyratron after the explosion of the propellant, and wherein said detonators each include a spark plug.

11. A mechanism as defined in claim 7 wherein said electrical means includes a thermistor, and a relay electrically connected between said thermistor and said ignition coil, and wherein said detonators each includes a spark plug.

12. A mechanism for propelling a shuttle in a loom comprising a shuttle, means for exploding a fluid propellant, a rod actuated by said explosion for propelling said shuttle, means actuated by the movement of said shuttle for operating said propellant exploding means, and means for absorbing a portion of the explosive impact applied to said rod, said impact absorbing means including a first plate fixed to said rod, a second plate slidably carried by said rod, a compression spring interposed between and connected to said plates, means for obstructing the movement of said second plate when said rod is actuated by the explosion whereby a portion of the explosive impact is absorbed in compressing said spring by the said plates, and means for releasing said plate obstructing means as said rod completes its shuttle propelling movement to permit said spring to assume an equilibrium condition.

13. A mechanism for propelling a shuttle in a loom between first and second terminal positions including a shuttle, means at the first and second terminal positions operative in alternate relationship for exploding a propellant, means including a rod at each of the first and second terminal positions actuated by such explosion for propelling said shuttle, means actuated by said shuttle as it moves into the first and second terminal positions for operating said propellant exploding means, means interposed between said shuttle actuated means and said propellant exploding means for delaying explosion of the propellant for a predetermined time period after said shuttle is received within said first and second terminal positions and means for absorbing a portion of the explosive impact applied to said rods including a cylinder disposed adjacent to each of the first and second terminal positions and through which said respective rods extend, a piston connected to each of said rods for movement within the respective cylinders, at least one opening extending through each of said pistons, and a hydraulic fluid contained within each of said cylinders for retarding the movement of said pistons and rods.

References Cited in the file of this patent UNITED STATES PATENTS I Blundell I an. 6, 1903 

